Lorentz-force actuated needle-free injection for intratympanic pharmaceutical delivery

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 113-118).Delivery of pharmaceuticals to the inner ear via injection through the tympanic membrane is a method of local drug delivery that provides a non-invasive, outpatient procedure to treat many of the disorders and diseases that plague the inner ear. The real-time controlled linear Lorentz-force actuated jet injector developed in the MIT BioInstrumentation lab was found to be a feasible technology for possible improvement over current intratympanic drug delivery methods. Jet injection holes using a nozzle with a 50 [mu]m orifice were found to be significantly smaller than those made using a standard, 0.31 mm (30-gauge) hypodermic needle. The feasibility of using the jet injector to deliver drug to the inner ear with less tissue damage than seen in standard procedures is shown offering an avenue for improved inner ear drug delivery methods and technology.by Alison Cloutier.S.M

A Lorentz-force actuated needle-free intraocular injection device

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 73-77).Intravitreal injection is a common treatment in ophthalmology, but it can lead to considerable patient anxiety and numerous complications. Lorentz-force actuated needle-free jet injection has been shown to successfully deliver fluid to various layers of skin, and, by its nature, may reduce intravitreal injection anxiety and complications. The challenges of adapting current Lorentz-force actuated needle-free jet injection technology to intravitreal injection were investigated using a previously developed jet injection system. Two iterations of an intravitreal injection-specific control scheme were designed, implemented, and tested. Several tools were developed in tandem with the research, including intravitreal injection 3D reconstruction software, actuator-jet transfer function generation software, and bench-top eye injection staging equipment. From injection trials into ex vivo rabbit eyes, we find that needle-free jet injection can be used for intravitreal drug delivery. The new system is capable of delivering 40 [mu]L of fluid to the posterior vitreous humor, with an injection duration less than 100 ms and scleral entry site less than 350 [mu]m in diameter. A relationship has been developed between injection parameters and eye damage metrics that can be used for future parameter optimization, minimizing damage to the eye.CD includes thesis in .pdf format.by James White.S.M

Needle free injection technology - An overview

Needle free injection technology was developed to reduce the number of needle stick accidents and associated problems. A comprehensive literature review was completed regarding needle free injection technology and its applications, advantages over needle injections, their components and types such as powder injection, liquid injection, depot or projectile injection. This review describes needle free injection technology involving the generation of force by using compressed gas upon actuation in order to deliver a drug at very high speed through a nozzle. This review also describes injection methods that use a spring load jet injector, battery powdered jet injector, and gas powdered jet injector. An overview of marketed products, recent trends and other needleless drug delivery systems is given. Needle free injection technology is growing and has the potential to make the administration of medicine more efficient, safe and convenient.   Type: Commentar

Needle free injection technology - An overview

Needle free injection technology was developed to reduce the number of needle stick accidents and associated problems. A comprehensive literature review was completed regarding needle free injection technology and its applications, advantages over needle injections, their components and types such as powder injection, liquid injection, depot or projectile injection. This review describes needle free injection technology involving the generation of force by using compressed gas upon actuation in order to deliver a drug at very high speed through a nozzle. This review also describes injection methods that use a spring load jet injector, battery powdered jet injector, and gas powdered jet injector. An overview of marketed products, recent trends and other needleless drug delivery systems is given. Needle free injection technology is growing and has the potential to make the administration of medicine more efficient, safe and convenient.   Type: Commentar

Modified Transdermal Technologies: Breaking the Barriers of Drug Permeation via the Skin

Transdermal drug technology specialists are continuing to search for new methods that can effectively and painlessly deliver larger molecules in therapeutic quantities to overcome the difficulties associated with the oral route, namely poor bioavailability due to hepatic metabolism (first pass) and the tendency to produce rapid blood level spikes (both high and low). Transdermal delivery can improve the therapeutic efficacy and safety of drugs by more precise (i.e., site-specific) way but spatial and temporal placement within the body is required to reduce both the size and number of doses necessary to achieve the objective of systemic medication through topical application to the intact skin surface. Modulation of formulation excipients and addition of chemical enhancers can increase drug flux but that is not sufficient to ensure delivery of pharmacologically effective concentration of drug therefore, several new active rate controlled TDDS technologies (electrically-based, structure-based, velocity-based, etc.) have been developed and commercialized for the transdermal delivery of ‘troublesome' drugs. This review article covers most of the new active transport technologies involved in enhancing the transdermal permeation into an effective DDS. In-depth analysis, formulation approaches, applications, advantages and disadvantages of these newer technologies are discussed. Keywords: Transdermal drug delivery, microneedles, macroflux, iontophoresis, ultrasound, powderject, skin abrasion. > Tropical Journal of Pharmaceutical Research Vol. 6 (1) 2007: pp. 633-64

A REVIEW ON NEEDLE FREE INJECTIONS

At present scenario many researchers are working to develop technology that promises to deliver the drug in more efficient and less painful way in order to produce the therapeutic effects. Needle-free injection systems are novel ways to introduce various medicines into patients without piercing the skin with a conventional needle. Needle free injection gives very effective injections for a wide range of drugs.  Needle free systems are designed to avoid the problems associated with conventional needles making them safer, less expensive, and more suitable. Additional benefits include very fast injection compared with conventional needles and no needle disposal issues. This review intends to throw light on the basic mechanisms by which this technology works, different types of technologies available at present and its applications. Peer Review History: Received 18 April 2017;   Revised 25 April; Accepted 5 May, Available online 15 May 2017 Academic Editor: Dr. Amany Mohamed Alboghdadly, Princess Nourah bint abdulrahman university, Riyadh, [email protected] UJPR follows the most transparent and toughest ‘Advanced OPEN peer review’ system. The identity of the authors and, reviewers will be known to each other. This transparent process will help to eradicate any possible malicious/purposeful interference by any person (publishing staff, reviewer, editor, author, etc) during peer review. As a result of this unique system, all reviewers will get their due recognition and respect, once their names are published in the papers. We expect that, by publishing peer review reports with published papers, will be helpful to many authors for drafting their article according to the specifications. Auhors will remove any error of their article and they will improve their article(s) according to the previous reports displayed with published article(s). The main purpose of it is ‘to improve the quality of a candidate manuscript’. Our reviewers check the ‘strength and weakness of a manuscript honestly’. There will increase in the perfection, and transparency. Received file:        Reviewer's Comments: Average Peer review marks at initial stage: 4.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewer(s) detail: Dr. Amany Mohamed Alboghdadly, Princess Nourah bint abdulrahman university, Riyadh, [email protected] Dr. Hebatalla Ibrahim Ahmed Abdel Hameed, Al-Azhar University, Faculty of Pharmacy (Girls), Nasr City, Cairo, Egypt, [email protected]

Evaluating delivery of a monoclonal antibody using a linear Lorentz-force actuated needle-free injector

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 53-55).The medical application of injection of monoclonal antibodies using a controllable auto-loading needle-free jet injector has been evaluated for two potentially limiting factors: viscosity of the formulation and shearing of the antibody during ejection. We used the Hepatitis B monoclonal antibody C86322M for its easy access and widespread usage. We used repeatability studies of glycerol at up to 200 m/s and 200 [mu]L delivery volume to demonstrate precision at viscosities up to 21.6x10-³ Pa-s. We determined that viscosity alone would not limit the jet injector's performance. Additionally, we evaluated the integrity of the antibody post-ejection using the enzyme-linked immunosorbent assay (ELISA) and gel electrophoresis methods. Using the ELISA method, we compared the ability of the antibody to bind to its specific antigen, HBsAg, both before and after ejection at multiple speeds. Changes in molecular size and charge of the monoclonal antibodies were evaluated by gel electrophoresis, more specifically with SDS polyacrylamide gels in reducing and non-reducing situations, native gel electrophoresis, and IEF gel electrophoresis. Most of these techniques revealed little to no change between pre-ejectate and ejectate migration, indicative of an unchanging molecular size and overall charge. However, with IEF gel electrophoresis, we observed two extra residues around a pI of 6.8. A change in charge due to alterations of protein side-chains may affect the stability of the molecule, and so this result is worth further pursuing on a quantitative basis. Despite this possibility, overall we have demonstrated that at 1 g/L, no significant aggregation or degradation results from jet ejection.by Tiffany Jin.S.B

Lorentz-force actuator for needle-free injection

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 67-68).The BioInstrumentation Laboratory at MIT developed a needle-free injector that is driven by a Lorentz-force actuator. The current model was able to generate pressures of up to 20 MPa in order to drive a jet of water based solution. In order to improve the needle-free injector, a new Lorentz-force actuator was designed and modeled using finite element analysis software. The new magnetic configuration included a radially-magnetized ring that generated a larger magnetic field across the airgap of the Lorentz-force actuator. Calculated peak forces were between 400 N and 600 N depending upon the position of the stroke length and the current density through the coil. Saturation in the steel core and casing, onsetting at a current density of about 108 A/m 2 , resulted in diminishing returns in force from an increasing current density. The rheological properties of poly(ortho) ester were measured for determining the feasibility of injecting viscous drug mediums. Of the two samples provided, the less viscous batch had a measured viscosity of 2.5 Pa-s and exhibited shear thinning at a shear rate of about 1000 s-1. Shear thinning has a large effect on the required pressure for injecting poly(ortho) ester at sufficient velocities. Finally, a benchtop experiment was designed and built to measure the force output of a BEI Kimco Lorentz-force linear actuator. A circuit was built to charge and discharge a capacitor that drives the output of the coil. Forces of up to 1000 N were measured at a stored capacitor voltage of 200 V. The time to peak force output was measured between 4 and 5 ms for high and low voltages respectively. Inefficient switching resulted in lower than expected forces below 40 V while increased resistance increased the damping of the overall system. Saturation was observed in the coil at voltages of 70 V and higher. The current capacity of the coil will continue to be pushed to the maximum stored value of 500 V.by Jonathan Michael Mendoza.S.B

Intradermal needle-free powdered drug injection

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 65-67).This thesis presents a new method for needle-free powdered drug injection. The design, construction, and testing of a bench-top helium-powered device capable of delivering powder to controllable depths within the dermis is presented. This device uses a jet of gas undergoing choked flow to entrain powder and subsequently penetrates through the skin for delivery of the powder. Different nozzle designs and orifice geometries are also explored. In vitro injection of polymer beads (1-5 [mu]im in diameter) into porcine tissue demonstrate the device's capability of drug delivery to depths of 260 to 5000 [mu]m. The jet parameters of nozzle orifice diameter and applied pressure are shown to affect injection depth, shape, and success rate. The presented device has the potential to be implemented with stabilized formulations of vaccines to address the cold chain problem-the cost and risk of transporting temperature sensitive vaccines to developing countries.by John Liu.S.M